ICP DAS USA PET-7060, User Manual

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Chapter 4 How to access ET-7000
PET-7000 DIO User Manual, May 2009, V1.00, EMH-013-10----------
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4.2. Using the Modbus protocol
4.2.1. Introduction
MODBUS is a master-slave bus system in which only one device (the master) actively
starts a transaction (query). The passive device (the slave) then sends a response. Most
SCADA Supervisor Control And Data Acuisition and HMI software can easily integrate
serial devices via the Modbus protocol, such as Citect, ICONICS, iFIX, InduSoft, Intouch,
Entivity Studio, Entivity Live, Entivity VLC, Trace Mode, Wizcon, Wonderware, etc.
The
PET-7000 controller includes the Modbus/TCP protocol, which is a variation of the
Modbus protocol that was developed in 1999 to allow the Internet community to access
Ethernet devices.
Modbus address for Modbus/TCP client access.